introduced true block and EOL comments

* The previous convention of !* ... *! are now true block comments,
  i.e. they are parsed faster, don't spam the goto table and allow
  embedding of exclamation marks - only "*!" terminates the comment.
* It is therefore now forbidden to have goto labels beginning with "*".
* Also support "!!" to introduce EOL comments (like C++'s //).
  This disallows empty labels, but they weren't useful anyway.
  This is the shortest way to begin a comment.
* All comment labels have been converted to true comments, to ensure
  that syntax highlighting works correctly.
  EOL comments are used for single line commented-out code, since it's
  easiest to uncomment - you don't have to jump to the line end.
  This is a pure convention / coding style.
  Other people might do it differently.
* It's of course still possible to abuse goto labels as comments
  as TECO did for ages.
* In lexing / syntax highlighting, labels and comments are highlighted differently.
* When syntax highlighting, a single "!" will first be highlighted as a label
  since it's not yet unambiguous. Once you type the second character (* or !),
  the first character is retroactively styled as a comment as well.

1 files changed, 0 insertions, 4 deletions

diff --git a/TODO b/TODO
index ff8d629..aef24dc 100644
--- a/TODO
+++ b/TODO
@@ -575,10 +575,6 @@ Features:
    Perhaps a few select local Q-Registers (-, _, ^X, ^R) should be
    accessible with the global reg syntax as well, so G- is equivalent
    to G.-?
- * Real block comments (!* ... *!) that don't spam the goto tables.
-   TECO-64 has end of line comments beginning with !! as well.
-   We may want both as 0<...> cannot be used to comment out all sorts
-   of blocks as it necessarily drives the parser.
  * `-` currently inverts the number sign in teco_state_start_minus().
    So --1 == 1 and --C == C.
    There is probably no need for this "feature" and an error